Combined rotary and reciprocatory drill



Nov. 29, 1932; J F, HAAS l COMBINED ROTRY A'ND RECIPROCATORY `DRIILL Filed Aug. 50, 191.50

Patented Nov; 29, 1932l UNITED STATES PATENT oFFlcE Y JOSEPH F. HAAS, 0F FOREST PARILYILLINOIS, ASSIGNOR TO WODACK ELECTRIC vTOOL CORPORATION, OF CHICAGO, ILLINOIS, A'CORPORATION 0F ILLINOIS COMBINED ROTARY AND RECIPROCATORY DRILL applicati@ mea August so, isso. serial No. 419,069. i

The invention relates generally to portable power operated drills and the general object 1s to provide a practical drill of this character adapted to produce either reciprocatory or rotary movement of a tool whereby7 to adapt the drill for a broad field of usefulness.

Another object` is to provide a reciproca- 4 tory drill unit of compact, rugged construction which ma be assembled and disassembled readily or inspection or repair and adapted to be detachabl associated with a rotary power source suc a rotary drill.

Other objects and advantages will be understood from the following description when taken in connection with the accompanying drawing in which:

Fig. 1 is a side elevational view of a drill embodying the invention in its preferred form.

Fig. 2 is a fragmental sectional view taken along the line 2-2 of Fig. 1.

Fig. 3 is -a sectional view taken along the line 3-3 of Fig. 1.

Fig. 4 is an enlar ed perspective view of the actuating cam o? the reclprocatory drill unit.

Fig; 5 is an enlarged perspective view 'of the cam follower which is adapted to cooperatewith the cam shown in Fig. 4.

While my invention is susceptible of embodiment in many different forms, I have shown in the drawing and will herein describe in detail one such embodiment with the understandin thaty the present disclosure is to be considered as an exemplification of the principles Aof the invention and is not intended to limit the invention to the embodiment illustrated. The scopeof the invention will be pointed out in the appended claims.

In the preferred form shown inthe drawing, the drill is electrically operated and consists of `two readily separable units, one of which is designated generally'by the numer- Ial and when taken alone constitutes a motor-driven rotary drill, while the other unit is designated generally by the reference numeral 11 and constitutes a reciprocatory drill adapted to receive rotary motion from 5 the chuck12 of the rotary drill unit 10 and as the spindle of to convert this rotary motion into reciprocatory motion in a star drill bit 13.

l The rotary drill unit 10 in the present case comprises a motor housing` 14, one end of which carries a trigger-grip handle 15 of well-known construction for controlling the operation of the motor contained in the housing. Secured to the other end of the housingis a gear box or housing 16 in which is mounted speed reduction lgearing (not shown) for driving a drill spindle 17 at a suitable speed. The dfrill spindle 17 is mounted in and projects from a cylindrical hub 18 which'is formed integrally with the gear box 16 and projects therefrom so as to actas a bearing for the spindle 17. l

On its projectingend the drill spindle 17 carries the chuck 12, the chuck being-preferably of the collet type in whicha plurality of jaws. 19 are moved radially into contact with a tool by rotation ofy a knurled sleeve 20 mounted/on the exterior of tlie chuck.

As above pointed out, the reciprocatory drill unit 11 is readily separable from the rotary drill unit 10 and as herein shown comprises a cylindrical casing 21 preferably formed from a casting, within one end of. which a hammer 22 (Fig. 2) is reciprocably mounted. To provide a slidable bearing for the hammer 22, a sleeve 23 is screw threaded y at 24 into one end of the casing 21. The sleeve 23 has a bore 25 of reduced `size formed therein at its opter end into which a reduced shank 26 of the drill bit 13 is slidably fitted so as to lie in the path of hammer'22.- The hammer 22 is yieldingly pressed toward the yshank 26 of the drill bit by an expensive coil spring 27 acting between the hammer and a shoulder 28 formed within the casing near the other end thereof, the movement of the hammer toward the ldrill bit being limited by a shoulder 29 formed at the inner end of the tool-receiving bore of the sleeve 23.4

To periodically withdraw the hammer 22 against the force of the spring 27 and release it* or impact with the tool shank'26, rotary cam means is preferably Iemployed, which -means isv mounted on `the end of the casing 21 opposite from the tool 13 and is arranged to act througha rod attached to the hammer 22. The connecting rod 30 is preferably formed integrally with the hammer 22 and projects axially through the spring 27 Aand the casing 21 and out of the opposite end of the casing. About the projecting end of the rod 30 a rotatable cam member 31 (Figs. 2 and 4) is positioned.

The cam member 31 is of cylindrical .form as shown in Fig. 4 with a. transverse wall 32 at one end to which an axial bearing sleeve 33 is connected. When the cam member 31 is in its operative position the bearing sleeve 33 surrounds the rod 30 and projects into an elongated bearing 34 (Fig. 2) formed in the casing 21, and in a counter bore 35 fn the casing, a ball thrust bea-ring 36 is positioned to engage the transverse wall 32 of the cam member. At its outer or open end, the cylindrical wall of the cam member 31 is shaped to provide twoangularly disposed cam surfaces 37 each extending through 180O and terminating abruptly as indicated in 38 in Fig. 4. Thus, a lcam follower 39 screwthreaded at 40 onto the projecting end of the rod 30 and having oppositely projecting arms 41 (Fig. 5) engaging the cam surfaces 37 may' be moved against the force of the spring 27 by rotation of the cam 31 relative to the rod 30. During such rotation of the cam 31, the rod 30 is held against rotation with the cam by a pair of key-ways 42 formed in the hammer 22 and engaged by keys 43 fixed in the bearing sleeve 23.

For the purpose of detachably connecting the units 10 and 11 together and forming a power-transmitting connection between the chuck 12 and the cam 31, a head 45 is rotatably mounted on the casing 21. The head 45,

in the present instance, is of cup-shaped form and is positioned about the cam 31 with its open end screw-threaded to the cam 31 as indicated at 46 in Figs. 2 and 4, and on its closedend the head 45 carries an axially projecting shank 47 adapted to extend into and be secured in the chuck 12. The shank 47 preferably has an enlarged outer end 48 which is engaged by the chuck jaws 19 to prevent axial withdrawal of the shank from the chuck.

Thus when the shank 47 is gripped in the chuck 12, the cam 31 will be rotated with the chuck. and to hold the casing 21 of the reciprocatory drill unit 11 against rotation with the cam 31, means is provided to interengage the casings of the two units. This means preferably comprises two arms 49 formed integrally with they casting which forms the casing 21and projecting from the opposite sides thereof, with a pair of rods 50, one fixed in each of the arms 49. The rods 50 extend arallel to each other along vthe opposite si es of the casing 21 past the cam 31 and its housing, and the projecting ends of the two rods 50 are adapted operatively to engage the gear housing 16 of the rotary drill unit.

To provide for such engagement a two part yoke 51 is clamped about the hub 18 of the rotary drill unt as shown in Figs. l, 2 and 3 and a pair of radial notches 52 formed in the parts of the yoke 51 are adapted to receive the. ends of the rods 50.

The impact of the arms 41 of the cam follower against the lower portion of the cam.

surfaces 37 is preferably cushioned by an expansive spring 41a positioned about the rod 30 within the cylindrical wall of the cam 31 and acting between the transver-se wall 32 of the cam member and the cam follower 39. The cushioning spring 41a also reduces the shock upon the chuck l2, particularly when the drill is running idle, since it-reduces the force with which the hammer 22 strikes the shoulder 29. l

Thus, to assemble the two units 10 and 11 the two projecting ends of the rods 50 may be slid axially into the notches 52 unt'l the shank 47 of the reciprocatory drill unit is positioned within the open jaws of the chuck 12, whereupon the chuck may be tightened securely about the shank 47. The rods 50 will then hold the casing 21 against rotation with the cam 31 when it is rotated by the chuck 12. Since the cam follower 39 is held against rotation through the action of the keys 43, such rotation of the chuck and the cam 31 will result in rapid reciprocation of the hammer 22 which will produce a rapid series of impacts upon the shank of the tool 13.

The rotary drill unit 10 is in the present `hand direction and the screw-threaded connection 46 between the head 45 and the cam member 31 and the connection 40 between the cam follower 39 and the rod 30 are therefore made by means of right hand threads, while the connection 24 between the guide sleeve 23 and the casing 21 is made by means of a left hand thread. This construction prevents disengagement of the parts during operation of the unit 11 and also facilitates the disassembly of the unit. Thus if it is desired to remove the cam follower 39, the guide sleeve 23 and the cam member 31 are engaged by suitable tools and the cam member is rotated in a left hand direction relative to the sleeve 23. As the cam member 31 is rotated, the abrupt shoulders 38 thereofengage and rotate the cam follower 39 in a left hand direction and thereby unscrew the cam follower from the rod 30.

The cam follower 39 may also be detached from the rod 30 by first removing the head 45 and then projecting a suitable tool through the tool socket 2 5 'to force the cam follower 39 axially away from the cam member 31.

When this has been done the cam follower 39 lar procedure may be followed in assembling the parts of the unit 11.

From the foregoin it will beclear that the construction of t e reciprocatory drill unit is of an unusually practical'character which is' of advantage to the user because of the ease with which it may be assembled and disassembled. It is also of advantage to the manufacturer since it enablesva one piece casing to be used. This results from the fact that the. detachable element of the springhammer assembly (that is, the cam follower 39) is held in its operative position b yielding means and may be forced away romits operative position and into a position wherein it may be readily detached for the purpose of assembling or disassembling' the unit.

The reciprocatory drill unit is ofa compact rugged construction due in a large measure to the usel of a one piece casing and it`may be'readily attached to or detached fromvthe rotary drill unit. Since the enlarged end 48 on the shank 47 cooperateswiththe chuck to hold the two units 1n the desired axial position, the rods 50 serve to prevent relative rotation of the casings of the two units. It

j will be noted that the assembling operation is quite simple because of the fact that the two units can be moved into operative position by a single axial moyement.

The two rods 50 being positioned on diametrically opposite sides of the axis of unit 11 serve to insure a balanced transmission of forces between the two units whereby to avoid breaking or distortion of the parts.

B providing the keys and key-ways in the guidi, sleeve andthe hammer, it is possible to make the bearing sleeve 33 on the cam member 31l unusuall long so as to insure proper operation of tlie cam. The long bearing sleeve also enables the cam and the attached shank 47 to function eilicientl and to cooperate with the rods 50 in maintaining the reciprocatory drill unit in the desired relation to the rotary drill unit. f

I claim as my invention: Y

l.y A tool of the class described comprising an elongated cylindrical casing, a hammer mounted in one end of said casing for limited lreciprocation longitudinally thereof, means providing a mounting for a drill bit at said end of the casing in the path of said hammer, means acting between said casing and said hammer to prevent relative rotation in one direction, a coiled spring actingbetween said hammer and said casing to force said hammer y toward said drill bit, a rod non-rotatabl fixed to said hammer and projecting throug said spring and out of the other end of said casing, a cam member surrounding the proj ect: ng end of said rod, a bearin sleeve connectedto said cam member an projecting along said rod substantially to the adjacent end of said spring, said casing having a bearing formed thereln to rotatably support said bearing sleeve, a thrust bearing acting between said cam member and said casing to receive the longitudinal thrust of the cam member, and a cam follower detachably secured on the projecting end of said rod to cooperate with said cam to periodically withdraw said hammer u on relative rotation of' said cam member an said casing.

2. A tool of the character described-comprisin a cylindrical casing, a hammer with- 1n sai casing, a sleeve removably secured in one end ofthe casing and surrounding and guiding said hammer for reciprocation, said sleeve and said hammer being inter-engaged to prevent relative rotation during such reciprocation, abutment means within said sleeve to limit movement of said hammer outwardly of the casing, a spring acting between said hammer and a shoulder inI said casing to press said hamm'er toward said abutment, a

rod non-rotatably secured to said hammer and projecting from the other end of said casing, a cam member surrounding said prjecting end-of the rod and mounted on said other end of the casing for rotation about the axis of the rod, and a cam follower detachably secured to said projecting end .of said rod and extending laterally therefrom to engage said cam. i

3. A device of the character described comprising a cylindrical casing, a hammer reciprocably and non-rotatably mounted therein, a removable abutment near one end" of the cas: ng limiting 'movement of sald hammer 1n a iirst direction, a sprlng mounted within the casing and operable to press said hammer frame and casing against relative rotation.t V

4. A two-unit drilling device comprising, in combination, a power-driven rotary-'drill unit having a' housing and a driven toolchuck, a detachably associated reciprocatorydrill unit having an elongated' casing, a hammer in said casing, means for operating said hammer including a non-rotatable cam element and a rotatable' cam element extendingv axiallyfromone end of said casing an adapted to be" engaged and rotated by said chuck andaspring acting against said casin and one of said cam elements to maintain s ai parts in assembled V relation when said units are separated, a pair ,of substantially rigid membersiextnding' longitudinally from said :z

asf

casing 'on opposite sides'of the axis thereof past said element and adapted to extend along opposite sidesof said housing', means on opposite sides of said housing engageable with said members to prevent relative rot-ation of said casing and said housing, and cooperating abutment means on said two units concentrically arranged about the axes of said casing and said drill-chuck operable to prevent separation of the two units longitudinally of said axes.

5. A hammer attachment for portable lpower drills comprisingan elongated body aving an axially slidable tool in the outer end thereof, a plunger reciprocable axially of the body in operative relation tosaid tool and projecting from the inner end of the body, an actuating spring for said plunger .tending to move it outwardly in the body, an annular member throughv which said projecting end of the plunger passes, a cam follower ixed on the plunger, said annular member having an inner cam face with which said follower coacts, and a hollow rotatable actuating element having said cam' member fixed thereto and coacting with said body to enclose the cam follower and the cam member, said body having means -for holding it in non-rotating relation to a power drill and said actuating element having means for detachably connecting it with the drill spindle. 6. A hammer attachmentA for portable power drills comprising an elongated body aving an axially slidable tool in one end, a plunger reciprocable axially of the body in operative relation to said tool and projecting AJfrom the opposite end of the body, a cam follower` fixed on the projecting end' of the plunger, a hollow rotatable actuating element providing a ch'amber for receiving said cam follower, one eid of said chamber having an. opening V.therein to receive the prpje'ctig end of said plunger and the other end of the chamber having-a closing end wall, said actuating element having adjacent the openend of the chamber a cam member rotatable with the element, said' cam follower coacting with said cam member in its rotation to move the plunger in one direction, a spring acting upon said plunger tending .to move it in the opposite direction, meansolrsaid clos- .ing end wall of said actuating elenentadaptedto-be detachably connected with the drivingspindle of a power driven drill, 'and a providing a detachable connection with a spindle of a power driven drill and said body havin means for engaging a part of said drill or holding the body against rotation.

8. A hammer attachment for rotatable drills comprising an elongated body having an axially slidable tool in the outer end thereoffa plunger reciprocable axially of the body in operative relation to said tool and projecting from the inner end of the body, a hollow rotatable actuating element bearing against the inner end of the body and encircling said projecting end of the plunger, said element having fixed thereto an annular cam member also encircling the plunger, a cam follower on the plunger coacting with said cam member, a spring acting on said plunger to hold said follower in engagement with the cam member, and a cushioning spring housed in said element and adapted to be engaged by said follower when released by said cam, said actuating element having means for engaging a part of said drill for holding the body against rotation. 4

' 9. A device of the class described comprising a rotary drill having. a housing and a driven tool chuck, a reciprocatory drill unit having a casing, a spring hammer in said casing, a rotatable actuating element for said hammer projecting from said casing and adapted 'to be drivingly connected to said chuck, a pair of rods secured on opposite sides of said casing and extending longitudinally past said element, and a clamp adapted to be secured on said housing andv roviding a pair of notches for Iengagement y said rods to prevent relative rotation of the casing and said housing. j

In testimony whereof, I have hereunto affixed my signature.

A JOSEPH F. HA'AS.

part on said body adapted to engage 'with a part on said drill to hold the bodyagainst rotation. si 7. A hammer attachment for rotatable drills comprising an elongated body having an axially.. slidable tool in the outer erd V thereof, a plunger reciprocable axially of the body in operative relation lto.., said tool and pro]ecting'from the inner end of the body, a hollow rotatable actuating element bearing against the inner end of the" body and enu 

